This invention relates to containers with removable lids, and particularly, to a lid that is not easily removed from a container by a child. More particularly, this invention relates to a canister with a lid-release control mechanism.
Many consumers want a container lid that can be removed easily by an adult but not by a child. It is hoped that child-resistant closure and container assemblies will make it more difficult for unauthorized children to remove a lid from a container and gain access to the contents of the container.
One problem with some conventional child-resistant lids is that a tool must be used to remove the lid from the container. Another problem with some designs is that it is necessary to deform the container or lid to gain access to the material in the container. It has been observed that consumers are eager for an easy on-easy off lid that is not easily removed from a container by a young child and that is removable by an adult without first using a tool or deforming either the container or the lid.
What is needed is a lid that can be automatically installed on a container and removed manually by an adult aware of the technique that must be followed to detach the lid from the container. A lid that is configured to hide the container engaging and locking means from sight when installed on the container and to require only minimal movement relative to the container during installation and removal would avoid shortcomings of conventional child-resistant container lid systems.
According to the present invention, a canister includes a lid for covering the open mouth of a container. The container includes a rim around the open mouth and a pair of helical lid guides appended to the rim. The lid is rotatable to engage the helical lid guides and retain the lid in place on the container. The lid includes a first guide follower that is arranged to move around the rim during rotation of the lid relative to the container and engage one of the lid guides to hold the lid on the container.
A first of the helical lid guides on the container rim includes a first stop face. The lid further includes a first lock tab for engaging the first stop face on the first helical lid guide to block continued rotation of the lid in the lid-removal direction during removal of the lid from the container. The lid also includes handgrip means for lifting the first lock tab away from the container to disengage the first stop face on the first helical lid guide. The barrier to rotation of the lid relative to the container is removed once the first lock tab disengages the first stop face. The handgrip means allows an operator to move the tab to a position above the first helical lid guide disengaging the first lock tab and the first stop face so that continued rotation of the lid relative to the container in the lid-removal direction is permitted.
In preferred embodiments, the second helical lid guide on the container rim has a second stop face. The lid also includes a second lock tab on the second helical lid guide for engaging the second stop face on the second helical lid guide to block continued rotation of the lid in the lid-removal direction during removal of the lid. The first and second lock tabs are located about the periphery of the lid so that during rotation of the lid the first lock tab engages the first stop face on the container at the same time that the second lock tab engages the second stop face on the container. Such engagement prevents an operator from turning the lid any further relative to the container in the lid-removal direction. Essentially, this barrier helps to prevent many unauthorized persons from removing the lid to open the container.
To remove the lid from the container, the operator must first know that the handgrip means on the lid must be used to lift the first and second lock tabs away from the container to disengage those lock tabs on the lid and the stop faces on the container and thereby take away the lid rotation barrier set up by the lock tabs and the stop faces. Once the lid has been lifted in this manner, the operator is once again able to begin rotating the lid relative to the container in the lid-removal direction until the lid is removed from the container.
Advantageously, the lid-release control mechanism of the present invention is applicable to a wide variety of container and lid assemblies. The lid-release control mechanism can be used to provide a limited access lidded container that can be opened easily by an adult without using a tool or deforming the container or lid. Also, the design allows the container to be lidded automatically during a container-filling process. Minimal rotation of the lid relative to the container is needed to engage and disengage the guide followers on the lid and the lid guides on the container.
Additional objects, features, and advantages of the invention will become apparent to those skilled in the art upon consideration of the following detailed description of preferred embodiments exemplifying the best mode of carrying out the invention as presently perceived.